Pressure indicator



K. s. JENsoN PRESSURE INDICATOR iled July 1'-, 1955 March 2, 1937.

Y /f/5 firm/M575,

f//Zw Patented Mar. 2, 1937 UNITED s'r'ATi-:s

PATENT( oFFlcE aovasss PRESSURE INDICATOR Application July 1, 1935, Serial No. 29,299 z emma] (ci. '1srn This invention relates to pressure indicators.

It is the general object of the invention to provide a novel and improved pressure indicator of cheap and simple construction, which can be used for roughly measuring the pressure of gas as in smoke flues for heaters, stoves, etc.

To this end, generally stated, the invention consists in the novel parts and novel combinations of parts, hereinafter defined in the claims and described in the following specification, made in connection with the accompanying drawing, wherein like reference characters refer to the same or similar parts throughout the various views, and, in which,

35 Fig. l is a perspective view illustrating a pressure indicator embodying the invention;

Fig. 2 is a view in front elevation of the said indicator showing the same as it will appear when in use for determining the pressure anthn a smoke flue for a heater, portions of the smoke flue being shown in vertical section;

Fig. 3 is a perspective view of the same indicator with the front part of the casing removed;

Fig. 4 is a detail in vertical section of cer- 5 tain of the parts of the indicator;

Fig. 5 is a vertical section showing other parts in detail;

Fig. 6 is a view in front elevation illustrating the vane used with the indicator shown in the previously described views;

Fig. 7 is a similar view illustrating an alternative form-of vane that may be used; Y

Fig. 8 is a perspective view illustrating a second type of indicator embodying the invention;

Fig.-9 is a view in side elevation of the indicator shown in Fig. 8 applied for use to a smoke iiue, the iiue being shown in vertical section;

Fig. 10 is a perspective view illustrating the indicator of Fig. 9 with the front part of the casing removed; and

Fig. 11 is a perspective view illustrating the vane used with the indicator of Fig. 8.

. Referring first to the embodiment of the invention illustrated in Figs. 1 to 6, there is provided a cylindrical casing including a back I2 and a front I3.` The back I2 has a forwardly extending circular flange I2a joining a circular disk portion and this flange is thinned or rabbeted at its outer forward portion to receive the cylin- 50 drical Wall of front I3. The forward face of front I3 is provided with a semi-circular opening |30. closed by a light I4 of glass, celluloid kor other transparent material. The cylindrical wall of front I3 considerably above the axial cen- 55 ter of the cylinder is equipped with a nipple I5 slits at 25a and 251: to receive the pintle.

forming a port IB communicating with the interior ofthe casing. Directly opposite the nipple l5 the cylindrical wall of front I3 is equipped with a tubular member I'i forming a port I8 communicating with the interior of the casing. The

nipple I5 is preferably provided with a shoulder I5a joining a reduced portion of the nipple outwardly therefrom by a converging flaring portion, while the tubular member I1 is provided with' a head lla at its outer end and is convexly grooved inwardly therefrom to form a'convenient handle by which the indicator may be held when in use. A set screw I mounted in the member I1 is provided for adjustably regulating the size ofthe port I8.

A semi-circular dial 20 is supported by spaced studs 2| from the casing back I2 so that calibrations 22 on this dial are exposed to view through the glazed opening I3a in casing front I3. Spacing thimbles 23 surrounding the studs 2| are interposed between the casing back I2 and dial zo.

The casing back I 2 at its central portion is provided with a pintle bearing I2b and dial 20 in opposition to the bearing i2b is provided with a similar pintle bearing 20a. A pintle or vane shaft. 24, pointed at both ends is located between the casing back l2 and dial 20 and the pointed ends of this pintle are received respectively within the bearings I2b and 20a. Mounted on pintle- 24 is a vane 25. This vane has at its central portion a pair of longitudinal slits and parts of the vane are oppositely grooved adjacent these The vane 25 has two radial arms extending outwardly from the pintle 24, the upper arm being bent somewhat out of the plane of the lower arm so as to cause the vane to normally balance as indicated in Figs. 2 and 3. The lower arm of the vane is slightly heavier than the upper arm and the lower arm is provided with an angular pointer finger 26, which works over the calibrations 22 on dial 20. When the vane is in its normal balanced condition, as lshown in Figs. 2 and 3,

the pointer finger 26 will point to the calibration "0 on the dial.

In Fig. 2 a smoke flue A for a stove or heater is illustrated. When it is desired to determine the draft conditions in this iiue, a-small aperture a is made in the flue whereupon the indicator is used. The operator grasps the tubular member I1 with his fingers received within the grooved portion thereof and presses his thumb against the head I'i to close the port I8. The nipple I5 is then inserted through the aperture a in the flue, whereupon the indicator is tilted until the pointer ringer 26 registers with the calibration O on dial 2U and thereupon the thumb of the operator is withdrawn from the` head I'Ia. If there is a proper draft condition in the flue A, the air in this flue will be somewhat under atmospheric pressure, so that air will tend to be drawn into the flue through the port I6 of nipple I5. As this occurs, of course, air will be supplied to the casing oi the indicator through the port I8. Air movement within the casing of the indicator between the inner mouths of the two ports I6 and I8 will cause the vane 25 to swing, thereby carrying the pointer linger to the right, as viewed in Fig. 2. The rapidity of air movement between the two ports will, of course, determine the position of the vane and the pointer nger and by comparing the position of the pointer linger with the calibrations 22 on dial 20, a rough indication will be given as to the pressure within flue A. If the pressure within nue A is above atmospheric pressure, which'would normally indicate a down draft rather than an up draft in the flue, the

pointer 26 would swing to the left of the O position and this would be clearly shown by the indicator.

Instead of using the'vane 25 and bending the two arms of the vane, so that they are out of alinement, to balance the vane normally so that the pointer is opposite the O position on the dial, the same result may be accomplished by use of vane 2T illustrated in Fig. 7. When this vane is 'used the pintle 24 is so connected to the vane that its central axis is located at the left side of the central plane of the vane so that although the two arms of the vane lie in the same plane, the vane normally stands with the pointer 26 opposite the O position of the dial.

Referring now to the form of the invention shown in Figs. 8 to l1, there is provided a cylindrical casing consisting of back 28 and front 29 of very similar construction to back and front of the casing previously described. The fiat surface of the front 29 is provided above the cylindrical center with a semi-cylindrical opening 29a closed by a light 30 of glass or other transparent material. Mounted at the top of the front 29 is an apertured knob 3| to which a. nipple 32 is connected, the nipple communicating with the aperture in the knob and the aperture in the knob communicating with the interior of the casing to form one of the ports of the device. A second port is formed by a small aperture 33 in the cylindrical wall of the front 29.

.A dial 34 is mounted behind the glass 30 so as to expose calibrations 35 to view through the glass and this dial is secured to the back 28 by means of spaced studs 36 carrying spacing thimbles 3'I. A pointed pintle 38 is mounted at the axial center of the cylindrical casing within pintle bearings formed in the back 28 and in the dial 34. Pintle 38 is mounted in an off center position after the manner shown in Fig. 7 and carries a vane 39 provided with a pointer finger 40 which works over the dial 34. The upper rear corner of the vane is preferably cut away at 39a to weight the vane slightly heavier below pintle 38 than above the same.

In using the indicator shown in Figs. 8 to l1, the nipple 32 is inserted through a small aperture in a flue B and the entire indicator may then be supported directly from the ue, as shown in Fig. 9. Movement of the vane 33 will be created by the passage of air through opening 33 into the casing of the indicator and thence through knob 3| and nipple 32 into the flue, or vice versa. The linger 40 registering with the calibration 35 on dial 34 will designate the variance in pressure from atmospheric in the fiue. When the finger 40 registers with calibrations 35 to the right of the O mark, this will indicate updraft movement of air within the liue and will also indicate that the pressure of air within the flue is below atmospheric pressure. When the linger 40 registers with the callibrations 35 to the left of the O position, this will indicate that the air is moving downwardly in the ue and that the pressure within the flue is above atmospheric pressure.

The device is particularly effective in installing household heaters and stoves, so as to determine whether or not proper draft conditions may be maintained for operation of such heaters and stoves in particular locations. The indicator, of course, is useful for many other purposes.

When the form of the device shown in Figs. 1 to 7 is used, it is easy to quickly adjust the device for proper use by regulation of the set screw I 9.

It will, of course, be understood that various changes may be made in the form, details, arrangement and proportions of the various parts Without departure from the scope of the present 2 invention. A

What is claimed is:

1. A pressure indicator including in combination a casing having a pair of spaced ports in communication with the interior thereof, a nipple communicating with one of said ports, said casing having a window therein, a dial mounted within said casing and exposed to View through said window, a pintle journaled within said casing between said dial and a surface of said casing, a vane mounted in a. longitudinally off center position on 'said pintle and having a portion freely movable between said two ports and a pointer carried by said vane and working over said dial.

2. A pressure indicator including in combination a casing having a pair of spaced ports in communication with the interior thereof, a nipple communicating with one of said ports, the front of said casing having a window therein, a dial mounted in spaced relation from the back of the casing for view through said window, a pintle journaled in said dial and said back, a vane mounted on said pintle and freely swingable between said two ports and a finger carried by said vane and working over said dial, said vane including two radial arms, one of which is slightly heavier than the other and one of which is disposed in a plane.at a slight angle to the plane of the other arm.

KENNETH S. JENSON. 

